The Mastiff had a different configuration from the early prototypes, featuring the pusher-propeller twin-boom configuration that would become common for combat surveillance UAVs. The Mastiff was introduced in 1975, but nobody seemed interested. 

The lack of activity was deceptive. The Israeli military were becoming increasingly interested in battlefield UAVs, and in response IAI decided they were interested in the concept as well. Tadiran and IAI found themselves in bitter competition for military battlefield UAV contracts. 

The Israeli military began to buy more Mastiffs, while IAI came up with a competitor with the appropriate name of "Scout" and sold it to the military as well. The Scout, which was also known as "Zahavan (Oriole)", had a similar configuration to the Mastiff, with a pusher propeller and a twin-boom tail. 

During Operation Peace for Galilee (1982) where they were confronted by Syrian SAMs, which were heavily sited in Lebanon's Bekaa Valley. All 28 SAM sites in the Bekaa were destroyed, however, partly through the use of Sampson decoys to get them to reveal their presence, and partly through reconnaissance information obtained by the Mastiff and Scout UAVs. 

After consolidating production of the Mastiff and Scout, the Malat company continued to sell them in slightly refined versions for over a decade. Both aircraft have fixed landing gear and are generally operated from runways, performing short landings using an arresting-wire hook, though they may be launched using a hydraulic catapult off the back of a truck, and recovered by a net. They both carry imaging sensors in a turret underneath the fuselage. 

The Mastiff and Scout remained in service with the Israeli Army until the early 1990s, when they were replaced by the Malat Searcher, also known as the "Meyromit (High Flier)". The Searcher looks almost identical to the Scout and Pioneer, but is scaled up, and in fact is well over twice the size of the Scout.